Temporary Lockdown’s ability is a single ability that creates two one-shot effects: one that exiles the permanents when the ability resolves, and another that returns the exiled cards to the battlefield immediately after Temporary Lockdown leaves the battlefield.

If Temporary Lockdown leaves the battlefield before its enters-the-battlefield ability resolves, no permanents will be exiled.

Auras with mana value 3 or greater attached to an exiled permanent will be put into their owners’ graveyards. Equipment with mana value 3 or greater attached to an exiled creature will become unattached and remain on the battlefield. Any counters on the exiled permanent will cease to exist.

Aura cards exiled this way will return to the battlefield attached to a permanent that they could enchant (based on their enchant ability) chosen by their owner. They cannot enchant any permanents that are entering the battlefield at the same time.

If a token is exiled, it ceases to exist. It won’t be returned to the battlefield. The mana value of a token that isn’t a copy of another permanent is always 0.

In a multiplayer game, if Temporary Lockdown’s owner leaves the game, the exiled cards will return to the battlefield. Because the one-shot effect that returns the cards isn’t an ability that goes on the stack, it won’t cease to exist along with the leaving player’s spells and abilities on the stack.