"When we got into the garage and into the house it looked like nearly a mock up of [the San Antonio Aquarium]", Leon Valley police chief Joseph Salvaggio was quoted as saying.
According to the post, aquarium staff caught up with the suspects in the auto park, who allegedly did not allow management to search their stroller or vehicle.
Police said all started early Saturday afternoon, when employees say there was something odd about a truck parked in a no parking zone.
The surveillance footage shows a man plucking the shark from the tank and carrying it away, off camera, still dripping water.
Surveillance video, which the aquarium posted on its Facebook page, caught the heist as it happened.
Police said a mock-up aquarium was uncovered at the suspect's house.
Salvaggio added: "But it turns out someone actually went inside the aquarium there in Leon Valley and stole a horn shark".
It is believed the man wanted to keep his newly-stolen shark so much that he even tried to dupe a police officer by claiming it wasn't the stolen shark at all, but an identical one he had bought. A third has not confessed, he said.
The thieves face felony theft charges, and police are probing to see if there are any other federal crimes related to stealing sharks.
A further post on Monday announced: "She's back home where she belongs!" Two men and a woman with a infant wandered through the facility with a baby stroller in tow. "And when we got into the garage and into the house, it looked like nearly a mock-up of (the aquarium)", he said. Police were working to get a warrant to retrieve the shark, Spellman said.
Horn sharks are commonly found in warm-temperate to subtropical waters and can grow to about four feet long. Staff applauded and cheered as Miss Helen made her homecoming.