Tomas Calderon is a S.H.I.E.L.D. agent. Despite the heavy casualties S.H.I.E.L.D. took during HYDRA's attack on the agency, he stayed loyal to his oath and continued his service in the remains of S.H.I.E.L.D. under Robert Gonzales. However, as another faction of S.H.I.E.L.D. led by Phil Coulson emerged, Calderon supported an attack on their new-found competitor. Once Coulson's base was taken over, Calderon was injured during an attack against Skye.
During the HYDRA Uprising, Calderon assembled a squadron of Quinjets in order to rescue the S.H.I.E.L.D. Academy from an HYDRA attack. During the Battle at the S.H.I.E.L.D. Academy, he witnessed HYDRA unleash an enhanced person on the S.H.I.E.L.D. defenders, and became wary of the danger enhanced people could be. He was able to kill the enhanced person and rescued the S.H.I.E.L.D. agents, including Anne Weaver.
Fighting Coulson's S.H.I.E.L.D.
Calderon was present when Agents Alphonso Mackenzie and Bobbi Morse returned to the base with Lance Hunter, who had discovered that they had been spying on Phil Coulson's S.H.I.E.L.D. Calderon took an immediate dislike to Hunter, and was furious when he later heard that Morse had allowed him to escape the base.
- "I'd like to offically withdraw my concerns about using the Dendrotoxin Gas, it's got style."
"If only someone was taking minutes."
- ―Tomas Calderon and Anne Weaver
As the plan went underway, Bobbi Morse contacted Robert Gonzales and Calderon, informing them that she had been forced to go to Plan B as Phil Coulson and Melinda May had discovered her betrayal, however she was able to steal the Toolbox. Gonzales explained that Lance Hunter's evac-pod had not yet been found before Calderon demanded to know if she had found Skye's location, to which she explained that she had not.
Bobbi Morse continued to make her way through the Playground base with the Toolbox until she was captured by Jemma Simmons. Meanwhile Alphonso Mackenzie used his skills to sabotage the base's security systems. Eventually the base was gassed, knocking out all the Agents inside and a bomb was detonated on the side of the base, injuring Mackenzie and Leo Fitz. Calderon joined Gonzales' team when they walked through the base and attacked and took over the Playground, the base from which Phil Coulson had been operating.
Once all of Coulson's Team were captured, with the exception of Melinda May who had stolen Bobbi Morse's gas-mask and was hiding somewhere in the base, Calderon and the rest of Robert Gonzales' council discussed the next step in their plan. Calderon once again expressed his desire to capture Agent Skye, who had been given the powers of earthquakes and appeared to be a danger to her own team. Once they learnt of Skye's location at the Retreat, Bobbi Morse insisted on joining Calderon in capturing her while Anne Weaver contacted Agent Oliver back on the Iliad to update him on their success.
Calderon and Bobbi Morse led a strike team to capture Skye. Morse ordered the men to only use I.C.E.R.s as Skye was still an Agent of S.H.I.E.L.D.; Calderon ignored the order and came armed with a fully loaded gun. While he was speaking to Morse about how he had saved Anne Weaver from an enhanced individual who HYDRA had unleashed at the S.H.I.E.L.D. Academy, they heard a gunshot which alerted them to Skye's location.
When they found Skye, Calderon disobeyed Bobbi Morse's orders and fired his gun at her, aiming to kill. However, Skye used her power to deflect the bullet, also causing a massive shockwave which threw Calderon and Morse backwards and destroyed a nearby tree. A piece of the tree imbedded itself in Calderon's shoulder, and as he lay wounded, Calderon witnessed Skye being teleported away from the scene by a mysterious eyeless man. Two days later, Calderon was still in critical condition.
Calderon had an unpleasant temperament. He was incredibly judgmental of and rude to others, even his fellow S.H.I.E.L.D. agents, although he showed loyalty to and was friends with Robert Gonzales and Anne Weaver and led the rescue mission at the academy. Gonzales was the only one who was able to have Calderon remain civil. Calderon had some skill in manipulation as shown when he told Gonzales that he wanted to bring Skye back when his real objective was to murder her. At the same time, he was prejudiced and discriminated against all gifted people, as shown by the way he tried to murder Skye without hesitation despite her being a loyal S.H.I.E.L.D. agent who meant no one any harm. Additionally, he showed enjoyment for other people's suffering, which was clear by his smiling when he saw Lance Hunter realizing that Bobbi Morse had betrayed him. While he argued with Bobbi and distrusted her because of her relationship with Hunter, he clearly respected her and her abilities, which he revealed to be the reason why he was so upset when Hunter escaped, as he knew Morse could have prevented him with her fighting skills if she had wanted to.
- SIG-Sauer P226: Calderon used a SIG-Sauer P226 as his sidearm when he broke into the Playground in order to take over the base. He also carried it to the Retreat in a mission to capture Skye. Despite Bobbi Morse ordered to use I.C.E.R.s to capture Skye, Calderon shot at her, making her powers get out of control to protect herself.
- Bulletproof Vest: Calderon wore a Bulletproof Vest during a mission to capture Skye. It prevented Calderon from being killed by a large chunk of wood that pierced his shoulder when Skye's powers got out of control to protect herself from a bullet that Calderon shot at her.
- S.H.I.E.L.D. (First Incarnation)
- S.H.I.E.L.D. (Second Incarnation)
In chronological order:
- Agents of S.H.I.E.L.D.