Referencing to the link bellow

http://blog.sqlauthority.com/2008/11/01/sql-server-stored-procedure-with-encryption-and-execution-plan/

if we create procedure like

CREATE PROCEDURE #RegularSP

AS

SELECT TOP 10 City

FROM Person.Address

GO

/* Create SP with Encryption */

CREATE PROCEDURE #EncryptSP

WITH ENCRYPTION

AS

SELECT TOP 10 City

FROM Person.Address

GO

/* Execute SP - Execution Plan Tab shows up */

EXEC #RegularSP

GO

and execute the #RegularSP then it will show the execution plan

and if we execute the #EncryptSP then the execution will be disappear.